Have you calibrated your hydrometer? It is not uncommon for them to be a few points off, so perhaps you don't even have an issue (other than a bad hydrometer).
If you are doing extract brews, some extracts ferment lower than others. In particular, using Laaglander extract results in a very high FG.
If you are doing all grain, the fermentability of the wort depends on the mash temperature, mash thickness, mash duration, and grains used.
Can you post a recipe that you have used, listing the grains and/or extracts, and the variety of yeast, and fermentation temperature (and mash temperature and thickness if doing all grain).
As for aeration of the wort, I believe that this if very necessary for liquid yeasts, but not so much for dry. I use an O2 bottle which provides enough oxygen in about 90 seconds. See http://maltosefalcons.com/tech/yeast...-and-practices for details of how to aerate and build up an adequate supply of yeast for pitching.

-a.

__________________
There are only 10 types of people in this world. Those that understand binary, and those that don't.

I've never used coopers but if it wasn't okay to do the job, there'd be a post on it here somewhere.....

Hmmmmmm. I normally do a extract with specialty grains and I used one liquid (WL) and since I have used same brand of dry yeast (nottingham). that stuff takes off.

Shouldn't matter much on the yeast so I read these days we got better batches than in past....

I'm not that great with c degree stuff but it appears to me the parts I know of your process seem okay. I have never had to rehydrate the dry stuff I have used yet. I just sprinkle on top while wort is spinning from a good stirr and she is good to go....

I do partial boils as well, the kits or recipe calls for 2 gallon or so but I have been doing 4 gallons since I read more the better... I should just move to doing 5 so my top off is just a little....(I'm considering that) I'm not sure on the half biol whether it could be part of issue as I said most kits and recipes I read say that.....

I hope somone else on here picks this up and can help more than I.

I'd only ask that you go thru a complete brew day from top to bottom and talk about any change points in fermentation time so that someone on here can help

it works but you need an inline air filter and it takes about 30 min. I recommend a oxygen bottle ($10 at hardware store). I use a propane valve b/c it was free and a sterile aquarium air-stone with fishtank tubing...the whole thing costs 20 bucks and each tank will oxygenate 25-30 batches.

I do (2) 30 second bursts of O2...so 1 minute total. Search the threads as there is a lot of info in past threads...

I second this one. I have the same setup that I bought at a homebrew supply. It came with a disposable oxygen tank regulator, sterile inline filter, a .5 micron stainless steel oxygenation stone and tubing. Just needed to buy a disposable oxygen tank at my local hardware store.

I just sanitize it in my bucket of Star-San before using it. Place it in my fermenter full of cooled wort, 60 seconds and I'm done.

Wyeast has done some testing on this subject. Thier results seem to suggest that the best way to aerate wort is through an oxygen pump and stone. But the interesting thing was that the second best way was simply to shake and slosh the wort for about a minute. Granted labor intensive, but effective.

__________________I love the sound of an airlock bubbling in the morning. It sounds like.....VICTORY.

Quote:

Originally Posted by TxBrew

It's now degenerating into nu uh and uh huhs and it no longer serves a point.

Wyeast has done some testing on this subject. Thier results seem to suggest that the best way to aerate wort is through an oxygen pump and stone. But the interesting thing was that the second best way was simply to shake and slosh the wort for about a minute. Granted labor intensive, but effective.

The problem is clear. Your thermometer is wrong. You need to measure in degrees Fahrenheit for beer to work.

Goose: I think it's safe to say that all home brewers aerate their wort. Some more effectively than others. I bet many don't even know they're doing it but it's happening at least to a certain extent. At the same time, the assumption that nearly all AG brewers are using an air pump or O2 tank is a little far fetched. Logic would say the majority of the brewers here are using the simplest of setups with a minimum of equipment. As simple as an air pump would be, it's well beyond the scope of the majority here. That would be like assuming that since there are so many posts with extravagant brew sculptures that nearly all brewers are using these rigs.

From an expert...
"Apparent Prematurely Stuck Fermentation - More often than not you're worrying. Many malt extracts are designed and produced to have a dextrin (unfermentable) content. This gives body to the beer. Some very fine all-malt extract beers will begin fermentation at 1.038 and finish as high as 1.013. Other high-gravity recipes will begin at 1.055 and be ready to bottle at 1.028. Aeration of the wort and choice of yeasts will make some difference, but usually minimal. Roll with the punches and bottle when fermentation has stopped or is negligible." - Papazian; The Complete Joy of Home Brewing, 3rd Edition; pg 359

The problem is clear. Your thermometer is wrong. You need to measure in degrees Fahrenheit for beer to work.

Goose: I think it's safe to say that all home brewers aerate their wort. Some more effectively than others. I bet many don't even know they're doing it but it's happening at least to a certain extent. At the same time, the assumption that nearly all AG brewers are using an air pump or O2 tank is a little far fetched. Logic would say the majority of the brewers here are using the simplest of setups with a minimum of equipment. As simple as an air pump would be, it's well beyond the scope of the majority here. That would be like assuming that since there are so many posts with extravagant brew sculptures that nearly all brewers are using these rigs.

From an expert...
"Apparent Prematurely Stuck Fermentation - More often than not you're worrying. Many malt extracts are designed and produced to have a dextrin (unfermentable) content. This gives body to the beer. Some very fine all-malt extract beers will begin fermentation at 1.038 and finish as high as 1.013. Other high-gravity recipes will begin at 1.055 and be ready to bottle at 1.028. Aeration of the wort and choice of yeasts will make some difference, but usually minimal. Roll with the punches and bottle when fermentation has stopped or is negligible." - Papazian; The Complete Joy of Home Brewing, 3rd Edition; pg 359

Nice book reference........ I have How to Brew 3rd edition....I guess I should consult Mr. Palmer this subject. I'll do so tomorrow and post what I find out.....